1. Field of the Invention
The present invention relates to a liquid jet head, a liquid jet apparatus, and a method for manufacturing the liquid jet head.
2. Description of the Related Art
As a typical example of a liquid jet head, for example, there is known an ink jet recording head that ejects ink droplets from nozzle openings by using pressure change caused by displacement of piezoelectric elements. Specifically, as disclosed in JP-A-2004-074740, an ink jet recording head is known which includes: a flow path unit which has a flow path forming board having therein pressure generation chambers, which are communicated with nozzle openings, and a vibration plate provided on one surface side of the flow path forming board; a nozzle plate which has the nozzle openings and is bonded to the flow path unit via an adhesive; piezoelectric elements (piezoelectric vibrators) which are arranged so as to correspond to the respective pressure generation chambers and are fixed to a support board; and a case head (a base) having therein an accommodation chamber for accommodating therein the piezoelectric elements (for example, see Patent Document 1).
A driving circuit that inputs a driving signal for driving the piezoelectric elements is mounted on a flexible printed circuit board, and the driving signal from the driving circuit is applied to the piezoelectric elements via the flexible printed circuit board.
However, the driving circuit mounted on the flexible printed circuit board is only able to dissipate heat from the driving circuit per se, the heat dissipation ability is limited. When a circuit loss exceeds the heat dissipation ability, the driving circuit may be destroyed by heat. Moreover, since a large heat dissipation area is required for securing the heat dissipation properties, there is a problem that miniaturization of the driving circuit is difficult.
Particularly, when the driving circuit is provided inside the case head as disclosed in Patent Document 1, the driving circuit is only able to dissipate heat within the case head and unable to dissipate the heat to the atmosphere, and thus the temperature of the driving circuit increases.
Such problems are similarly found in other liquid jet heads ejecting liquid other than ink as well as the ink jet recording head.